Various aspects of phospholipid metabolism in the gastric mucosa scrapings and in various cell-enriched fractions will be invesigated: (a) The relative activities of various acyl CoA acyl transferases and the content of palmitoyl CoA and oleoyl CoA in studies directed at obtaining a better understanding of how the gastric mucosa obtains its high content of dipalmitoyl phosphatidylcholine; (b) The importance of the phosphatidylethanolamine to phosphatidylcholine biosynthetic pathway; (c) The activities of gastric phospholipase C and phospholipase A2 in hydrolysis of phosphatidylinositol.